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Dr Muhamed-Kheir Taha @ MRF's Meningitis and Septicaemia 2019

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New generation of complement inhibitors-implications for clinical practice,vaccination policy

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Dr Muhamed-Kheir Taha @ MRF's Meningitis and Septicaemia 2019

  1. 1. The new generation of complement inhibitors and implications for clinical practice and vaccination policy Muhamed-Kheir TAHA MD, PhD Institut Pasteur Invasive Bacterial Infections London MRF Meeting 06/11/2019
  2. 2. Activation of the complement - Humoral innate immunity system - Acute-phase proteins -19 plasma and at least 9 membrane proteins Harris et al., Molecular Immunology 102 (2018) 89–119
  3. 3. Complement pathophysiology AD, Alzheimer’s disease AMD,Age-related macular degeneration DAMP, damage-associated molecular pattern; DDD, dense deposit disease; PAMP, pathogen-associated molecular pattern; PMN, polymorphonuclear cell; PNH, paroxysmal nocturnal hemoglobinuria; SLE, systemic lupus erythematosus. Ricklin &Lambris J Immunol. 2013
  4. 4. Harris et al., Molecular Immunology 102 (2018) 89–119 Pipeline for anti-complement drugs in the kidney, eye and vasculature Half-life of ravulizumab is 4 times longer than that of eculizumab (Lee et al., Blood, 2016)
  5. 5. Compstatin Complement Inhibition (inhibition of C3b deposition) on PNH RBC impact on both pathways Complement Activation on PNH RBC Lysis of PNH RBC - Insertion of C5b-9 MAC (intravascular hemolysis) - Opsonization with C3b (extravascular hemolysis) No Complement activation CD55 (C3b) CD59 (MAC) No lysis Eculizumab Complement Inhibition (C5 inhibition) on PNH RBC Lysis of PNH RBC is still occurring Opsonization with C3b (extravascular hemolysis) Complement inhibition and hemolysis in PNH
  6. 6. Risk groups for IMD Medical reasons - Close contacts of patients with IMD; - Subjects with a terminal complement deficiency or who are receiving anti-C5 treatment (and other future anti-complement treatment) - Subjects with other complement deficiencies (properdin Factor D) - Subjects with anatomical or functional asplenia; - Subjects who received a hematopoietic stem cell transplantation - HIV - Association with viral infection (flu) Occupational/societal reasons Travellers, pilgrims, mass gathering events, military, laboratory staff working on meningococci, MSM, Students Epidemic Situations
  7. 7. Complement and IMD Inherited and drug induced complement deficiencies. - 13% of IMD revealed complement deficiencies in South Africa (Owen et al., S Afr Med 2012). - One third of group Y IMD revealed complement deficiency France (Le Bastard et al., Pathol Biol, 1989 ). - 7/22 (32%) patients with NG IMD had complement deficiency or abnormal complement testing results (McNamara et al.,, Open Forum Infect Dis 6, 2019). - Among 160 patients with complete TPD; 56 patients (39%) showed confirmed IMD (France 1999-2015)(Rosain et al., J.Infect Dis 2017) - 16 patients in England with inherited or acquired complement deficiencies (2008-2017) (Ladhani et al., BMC Infect Dis 2019).
  8. 8. Complement deficiencies and IMD: Isolates Type of deficiency N° of isolates/episodes (patients) Isolates (n) Fatal cases TPD 63 (59) B(19); C(2); Y(29); W(9); E(4); NG(1) 1 Factor D 1 (1) B (1) 0 Properdin 1 (1) Y (1) 1 Eculizumab 3 (3) Y(2); C(1) 0 Rosain et al., J.Infect Dis 2017, El Sissy et al., Frontiers in Immunology 2019) : France 1999-2018 Type of deficiency N° of isolates/episodes (patients) isolates Inherited 11(8) B(3); Y(7); NG(1) Eculizumab 9 (8) B(3+3NG); Y(1); W(1); E(1) Ladhani et al., BMC Infect Dis 2019 : England 2008-2017 • Heterogeneous isolates • Frequent Y, E and NG isolates • Only 21% belonging hyper-invasive CC (France)
  9. 9. Coverage of serogroup B and E isolates of the TPD patients by the 4CMenB vaccine 1 2 4 8 16 32 64 128 256 512 Before After hSBAtitreslog2 Serogroup ESerogroup B Data NRC, Institut pasteur
  10. 10. Immunogenicity of MCC in a patient with aHUS on eculizumab therapy Zlamy et al., Pediatr Transplantation 2012: A four-yr-old boy presented with aHUS • TCC concentration reflects the ability to activate the complement system • But SBA response seems to be impaired under treatment Terminalcomplementconcentration(C5b-9) inhealthydonors260and890lg/lL Reduction of eculizumab doses TCC SBA
  11. 11. Courtesy from Prof R. Borrow Parikh SR et al. Pediatrics. 2017 Sep;140(3). pii: e20162452.  Case of IMD due to a vaccine-preventable and penicillin-resistant strain in a fully immunised young adult (22 years) on long-term complement inhibitor therapy and daily penicillin chemoprophylaxis.  First case of meningococcal group B vaccine failure in a young adult receiving Eculizumab for aHUS.  Developed IMD due to capsular group B 4 months after receiving 2 doses of 4CMenB vaccine while on oral penicillin prophylaxis.  Strain ST-162 (pathogenic potential).  Capsular gene SiaDb interrupted by an insertion sequence.  PenA allele contained 3 mutations associated with reduced penicillin sensitivity.  PenA allele previously associated with N. gonorrhoeae.  Strain confirmed covered by 4CMenB by MATS by NHBA antigen. Penicillin-resistant case of IMD in patient on Eculizumab therapy
  12. 12. Penicillin resistant in England, Wales and Northern Ireland (2010/11-2017/18) 66.67 68.63 60.96 61.14 68.62 52.01 67.13 65.49 31.97 31.13 37.06 36.88 30.21 43.02 29.70 32.07 1.36 0.25 1.97 1.98 1.17 4.97 3.17 2.45 2010/11 (N=513) 2011/12 (N=408) 2012/13 (N=456) 2013/14 (N=404) 2014/15 (N=513) 2015/16 (N=523) 2016/17 (N=505) 2017/18 (N=368) %OFISOLATES EPIDEMIOLOGICAL YEAR Susceptible (≤0.06 mg/L) Intermediate Resistance (0.06 mg/L < MIC ≤ 0.25 mg/L) Resistant (>0.25 mg/L) Courtesy from Prof R. Borrow. PHE unpublished data.
  13. 13. Susceptibility to penicillin G 34% 22% 0 25 50 75 100 Susceptible Intermediate Invasive TPD % Data NRC, MK Taha, Institut pasteur, Unpublished data
  14. 14. 0.5h 3h 6h 8h 5 6 7 8 9 Time(h) untreated 250 000 IU/Kg Penicillin is still effective against intermediate (resistant) isolates (mouse model) Susceptible isolate (MIC <0.064 mg/L) InvivoBacterialgrowth Belkacem et al., Antimicrob Agents Chemother 2016). Penicillin treatment 0.5h 3h 6h 8h 5 6 7 8 9 Time(h) Intermediate (resistant) isolate (MIC 0.5 mg/L) Penicillin treatment Mice infected i.p. with isogenic susceptible or intermediate isolates (MIC0.5mg/L) 50 000 IU/Kg 100 000 IU/Kg
  15. 15. Conclusions (1) • Increasing evidence of association of complement activation and degenerative diseases • Anti-complement treatment may be benefic • Complement deficiencies can be associated with increase susceptibility to IMD. • Serogroup Y isolates predominate but NG can be important under anti- complement treatment • Explore complement systematically when IMD is provoked with non hyperinvasive isolates. • Explore complement systematically if IMD with vaccine preventable serogroup in vaccinated patients. • If an inherited complement deficiency confirmed in the patient then explore the members of the family. • Exploration of not only the determination of the CH50 activity but also the alternative pathway.
  16. 16. • Vaccination of subjects with complement deficiencies (inherited and acquired) against ACWY and B • Vaccination in not enough. Antibiotic treatment is required (High dose penicillin V ≥ 250 000 IU/Kg/day). • Rescue antibiotics (i.e. self-treatment with a treatment course of amoxicillin (+ penicillin), ciprofloxacin or other antibiotics to be defined when unwell)? • Vaccination of household contacts of subjects with complement deficiencies (cocooning strategy). Conclusions (2)

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